First find the area of the facing side
Area = area of bottom rectangle + area of the trapezium at the top
= 5 * 12 + 1/2 *(7+12)*(15-5)
= 60 + 1/2 * 19 * 10
= 60 + 95 = 155
Now multiply by the length
Volume = 155 * 8 = 1240 cm^3 (answer).
